package com.lanou3g.code0424;

import java.util.HashSet;
import java.util.Set;

/**
 * Created by dllo on 18/4/24.
 */
public class Main {
    public static void main(String[] args) {
        Set<String> strings = new HashSet<>();
        strings.add("aaa");
        strings.add(null);
        strings.add(null);

        System.out.println(strings.size());
        for (String string : strings) {
           // if (string == null)
            System.out.println(string.length());   //如果不加以判断是否存在null,就会崩溃
            System.out.println(string);

        }
    }
}
